Note that even pros must use some tricks to run something of it on the modern hardware, so it appears as it's still mostly an experimental research platform?
"I am typing this in acme in 9vx running
on FreeBSD, using the rio port in P9P for my window manager.
Because I'm away from my home network, I'm running 9vx
with the the root on my local machine. When I'm at home, I
use 9vx booting with its root taken from a real Plan 9 file
server. I also run it on qemu fairly often."
http://www.mail-archive.com/9fans@9fans.net/msg17086.html
"I am typing this in acme in 9vx running on FreeBSD, using the rio port in P9P for my window manager. Because I'm away from my home network, I'm running 9vx with the the root on my local machine. When I'm at home, I use 9vx booting with its root taken from a real Plan 9 file server. I also run it on qemu fairly often."